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#2265 (Misleading minimum viscosity with Smagorinsky scheme ?) – NEMO

Opened 4 years ago

Closed 3 years ago

Last modified 10 months ago

#2265 closed Defect (fixed)

Misleading minimum viscosity with Smagorinsky scheme ?

Reported by: jchanut Owned by: gm
Priority: low Milestone:
Component: LDF Version: v4.0
Severity: minor Keywords: v4.0
Cc:

Description (last modified by nicolasmartin)

Context

From ldfdyn.F90, the Laplacian Smagorinsky scheme (formula 32) scales the viscosity minimum with the local velocity speed (U) such that:

A = MAX(Asmag, rn_minfac * U * dx / SQRT(4.) )

With the default namelist value rn_minfac=1., it is therefore assumed a Reynolds number (Re) that equals 2., a pretty low value that leads to values well above what gives the Smagorinsky scheme with a standard coefficient. One would have expected a Reynolds number that matches what is used with formula (31), i.e. Re=12 or... alternatively a default value rn_minfac=0.16.
Was this done on purpose ? Did I missed something ?

Commit History (2)

ChangesetAuthorTimeChangeLog
12201smasson2019-12-12T09:51:33+01:00

trunk: correct [12194], see #2265

12194smasson2019-12-11T17:21:56+01:00

trunk: minor bugfix in ldfdyn, see #2265

Change History (6)

comment:1 Changed 4 years ago by nicolasmartin

  • Description modified (diff)

comment:2 Changed 4 years ago by clevy

  • Owner changed from systeam to gm
  • Status changed from new to assigned

comment:3 Changed 3 years ago by smasson

In 12194:

Error: Failed to load processor CommitTicketReference
No macro or processor named 'CommitTicketReference' found

comment:4 Changed 3 years ago by smasson

  • Resolution set to fixed
  • Status changed from assigned to closed

comment:5 Changed 3 years ago by smasson

In 12201:

Error: Failed to load processor CommitTicketReference
No macro or processor named 'CommitTicketReference' found

comment:6 Changed 10 months ago by nemo

  • Keywords v4.0 added
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